<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<div id="app">
    <!--性别：
    <input type="radio" name="sex" value="男" v-model="select"> 男
    <input type="radio" name="sex" value="女" v-model="select"> 女
    <p>选中了谁：{{select}}</p>-->
    <select v-model="selected">
        <option value="" disabled>---请选择---</option>
        <option>A</option>
        <option>B</option>
        <option>C</option>
    </select>
</div>
<script src="https://cdn.jsdelivr.net/npm/vue@2.5.21/dist/vue.min.js"></script>
<script>
    var vm = new Vue({
        el: "#app",
        data: {
            selected: 'D'
        },
        methods: {}
    });
</script>
</body>
</html>
